A marble bag contains 3 red marbles, 4 gray marbles, 6 white marbles, and 5 black marbles. What is the probability of randomly drawing a red marble and then a gray marble if the first marble is replaced?​

Charlie is at an amusement park that has 18 different rides. each ride costs $1.75. the function c(r) = 1.75r represents the total amount of money that charlie will spend if he goes on r rides, but he never goes on the same one more than once. what domain and range are reasonable for the function?